EuF3 纳米晶/PNIPAm复合水凝胶的制备及荧光温敏性能

以十一烯酸为表面活性剂, 采用液体-固体-溶液法(LSS)制备了EuF3纳米晶; 将其用CCl4处理, 得到表面修饰有C-Cl基团的功能化EuF3纳米晶; 通过原子转移自由基聚合(ATRP)制备EuF3 /聚N-异丙基丙烯酰胺(EuF3/PNIPAm)复合温敏水凝胶. 采用HRTEM, XRD, FTIR, DSC及PL等对EuF3 纳米晶及EuF3/ PNIPAm 复合凝胶的微观结构与性能进行了表征, 用变温荧光光谱研究了环境温度对复合凝胶荧光性能的影响. 结果表明, EuF3纳米晶呈六方相晶型; 粒径呈多分散分布, 且相对集中于10, 20和50 nm. 该复合凝胶的较低临界溶解温度(LCST)随纳米晶含量的增加而下降, 环境温度与纳米晶含量对复合凝胶的荧光特性产生明显影响.

Preparation of EuF3 Nanocrystals/PNIPAm Complex Hydrogel and Its Thermosensitive Fluorescent Performance

EuF 3 nanocrystals were synthesized with undecylenic acid as surfactant,via liquid-solid-solution synthesis(LSS) strategy,then they were treated with CCl 4 to obtain reactive EuF 3 nanocrystals decorated with C-Cl groups on their surface.A series of complex hydrogels of EuF 3 nanocrystals/PNIPAm with different contents of EuF 3 nanocrystal were prepared via atom transfer radical polymerization(ATRP) method.The microstructure and performance of the EuF 3 nanocrystal and the complexes hydrogels were characterized by HRTEM,XRD,FTIR,DSC and PL.The results suggest that the nanocrystal is hexagonal EuF 3 and size polydisperse,the main size of which is about 10,20 and 50 nm.With the increased content of nanocrystal,the lower critical solution temperature(LCST) of complex hydrogel decreased.The fluorescence performance of complex hydrogels was influenced greatly by both the ambient temperature and the content of nanocrystal.